From 3de7693865774596b4471b92e879a2df4fca7e18 Mon Sep 17 00:00:00 2001 From: Geoffrey Noer Date: Fri, 3 Jan 1997 22:23:08 +0000 Subject: [PATCH] Fri Jan 3 14:20:05 1997 Geoffrey Noer * mn10300-tdep.c (mn10300_push_arguments): rewrote also removed code elsewhere that made use of RP_REGNUM --- gdb/ChangeLog | 5 + gdb/mn10300-tdep.c | 353 ++++++++++++++++++++++++++++++++++++++++++++- 2 files changed, 353 insertions(+), 5 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index 91342424caf..6e6ef60ed15 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,8 @@ +Fri Jan 3 14:20:05 1997 Geoffrey Noer + + * mn10300-tdep.c (mn10300_push_arguments): rewrote + also removed code elsewhere that made use of RP_REGNUM + Tue Dec 31 15:19:32 1996 Geoffrey Noer * config/mn10300/tm-mn10300.h: more small register fixes diff --git a/gdb/mn10300-tdep.c b/gdb/mn10300-tdep.c index 6fb0be8afe3..fe32fa08b2f 100644 --- a/gdb/mn10300-tdep.c +++ b/gdb/mn10300-tdep.c @@ -1,5 +1,5 @@ -/* Target-dependent code for the NEC MN10300 for GDB, the GNU debugger. - Copyright 1996, Free Software Foundation, Inc. +/* Target-dependent code for the Matsushita MN10300 for GDB, the GNU debugger. + Copyright 1996, 1997 Free Software Foundation, Inc. This file is part of GDB. @@ -15,9 +15,7 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software -Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ - -/* Contributed by Geoffrey Noer, noer@cygnus.com */ +Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ #include "defs.h" #include "frame.h" @@ -47,36 +45,259 @@ struct prologue_info struct pifsr *pifsrs; }; +static CORE_ADDR mn10300_scan_prologue PARAMS ((CORE_ADDR pc, + struct prologue_info *fs)); + +/* Function: scan_prologue + Scan the prologue of the function that contains PC, and record what + we find in PI. PI->fsr must be zeroed by the called. Returns the + pc after the prologue. Note that the addresses saved in pi->fsr + are actually just frame relative (negative offsets from the frame + pointer). This is because we don't know the actual value of the + frame pointer yet. In some circumstances, the frame pointer can't + be determined till after we have scanned the prologue. */ + static CORE_ADDR mn10300_scan_prologue (pc, pi) CORE_ADDR pc; struct prologue_info *pi; { + CORE_ADDR func_addr, prologue_end, current_pc; + struct pifsr *pifsr; + int fp_used; + + printf("mn10300_scan_prologue start\n"); + + /* First, figure out the bounds of the prologue so that we can limit the + search to something reasonable. */ + + if (find_pc_partial_function (pc, NULL, &func_addr, NULL)) + { + struct symtab_and_line sal; + + sal = find_pc_line (func_addr, 0); + + if (func_addr == entry_point_address ()) + pi->start_function = 1; + else + pi->start_function = 0; + +#if 0 + if (sal.line == 0) + prologue_end = pc; + else + prologue_end = sal.end; +#else + prologue_end = pc; +#endif + } + else + { /* We're in the boondocks */ + func_addr = pc - 100; + prologue_end = pc; + } + + prologue_end = min (prologue_end, pc); + + /* Now, search the prologue looking for instructions that setup fp, save + rp, adjust sp and such. We also record the frame offset of any saved + registers. */ + + pi->frameoffset = 0; + pi->framereg = SP_REGNUM; + fp_used = 0; + pifsr = pi->pifsrs; + + for (current_pc = func_addr; current_pc < prologue_end; current_pc += 2) + { + int insn; + + insn = read_memory_unsigned_integer (current_pc, 2); + + if ((insn & 0x07c0) == 0x0780 /* jarl or jr */ + || (insn & 0xffe0) == 0x0060 /* jmp */ + || (insn & 0x0780) == 0x0580) /* branch */ + break; /* Ran into end of prologue */ + if ((insn & 0xffe0) == ((SP_REGNUM << 11) | 0x0240)) /* add ,sp */ + pi->frameoffset = ((insn & 0x1f) ^ 0x10) - 0x10; + else if (insn == ((SP_REGNUM << 11) | 0x0600 | SP_REGNUM)) /* addi ,sp,sp */ + pi->frameoffset = read_memory_integer (current_pc + 2, 2); + else if (insn == ((FP_REGNUM << 11) | 0x0000 | 12)) /* mov r12,fp */ + { + fp_used = 1; + pi->framereg = FP_REGNUM; + } + else if ((insn & 0x07ff) == (0x0760 | SP_REGNUM) /* st.w ,[sp] */ + || (fp_used + && (insn & 0x07ff) == (0x0760 | FP_REGNUM))) /* st.w ,[fp] */ + if (pifsr) + { + pifsr->framereg = insn & 0x1f; + pifsr->reg = (insn >> 11) & 0x1f; /* Extract */ + + pifsr->offset = read_memory_integer (current_pc + 2, 2) & ~1; + + pifsr++; + } + + if ((insn & 0x0780) >= 0x0600) /* Four byte instruction? */ + current_pc += 2; + } + + if (pifsr) + pifsr->framereg = 0; /* Tie off last entry */ + + printf("mn10300_scan_prologue end \n"); + + return current_pc; } +/* Function: init_extra_frame_info + Setup the frame's frame pointer, pc, and frame addresses for saved + registers. Most of the work is done in scan_prologue(). + + Note that when we are called for the last frame (currently active frame), + that fi->pc and fi->frame will already be setup. However, fi->frame will + be valid only if this routine uses FP. For previous frames, fi-frame will + always be correct (since that is derived from mn10300_frame_chain ()). + + We can be called with the PC in the call dummy under two circumstances. + First, during normal backtracing, second, while figuring out the frame + pointer just prior to calling the target function (see run_stack_dummy). */ + void mn10300_init_extra_frame_info (fi) struct frame_info *fi; { + struct prologue_info pi; + struct pifsr pifsrs[NUM_REGS + 1], *pifsr; + int reg; + + printf("mn10300_init_extra_frame_info start\n"); + + if (fi->next) + fi->pc = FRAME_SAVED_PC (fi->next); + + memset (fi->fsr.regs, '\000', sizeof fi->fsr.regs); + + /* The call dummy doesn't save any registers on the stack, so we can return + now. */ + if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) + return; + + pi.pifsrs = pifsrs; + + mn10300_scan_prologue (fi->pc, &pi); + + if (!fi->next && pi.framereg == SP_REGNUM) + fi->frame = read_register (pi.framereg) - pi.frameoffset; + + for (pifsr = pifsrs; pifsr->framereg; pifsr++) + { + fi->fsr.regs[pifsr->reg] = pifsr->offset + fi->frame; + + if (pifsr->framereg == SP_REGNUM) + fi->fsr.regs[pifsr->reg] += pi.frameoffset; + } + + printf("mn10300_init_extra_frame_info end\n"); } +/* Function: frame_chain + Figure out the frame prior to FI. Unfortunately, this involves + scanning the prologue of the caller, which will also be done + shortly by mn10300_init_extra_frame_info. For the dummy frame, we + just return the stack pointer that was in use at the time the + function call was made. */ + CORE_ADDR mn10300_frame_chain (fi) struct frame_info *fi; { + struct prologue_info pi; + CORE_ADDR callers_pc, fp; + + printf("mn10300_frame_chain start\n"); + + /* First, find out who called us */ + callers_pc = FRAME_SAVED_PC (fi); + /* If caller is a call-dummy, then our FP bears no relation to his FP! */ + fp = mn10300_find_callers_reg (fi, FP_REGNUM); + if (PC_IN_CALL_DUMMY(callers_pc, fp, fp)) + return fp; /* caller is call-dummy: return oldest value of FP */ + + /* Caller is NOT a call-dummy, so everything else should just work. + Even if THIS frame is a call-dummy! */ + pi.pifsrs = NULL; + + mn10300_scan_prologue (callers_pc, &pi); + + printf("mn10300_frame_chain end\n"); + + if (pi.start_function) + return 0; /* Don't chain beyond the start function */ + + if (pi.framereg == FP_REGNUM) + return mn10300_find_callers_reg (fi, pi.framereg); + + return fi->frame - pi.frameoffset; } +/* Function: find_callers_reg + Find REGNUM on the stack. Otherwise, it's in an active register. + One thing we might want to do here is to check REGNUM against the + clobber mask, and somehow flag it as invalid if it isn't saved on + the stack somewhere. This would provide a graceful failure mode + when trying to get the value of caller-saves registers for an inner + frame. */ + CORE_ADDR mn10300_find_callers_reg (fi, regnum) struct frame_info *fi; int regnum; { + printf("mn10300_find_callers_reg\n"); + + for (; fi; fi = fi->next) + if (PC_IN_CALL_DUMMY (fi->pc, fi->frame, fi->frame)) + return generic_read_register_dummy (fi->pc, fi->frame, regnum); + else if (fi->fsr.regs[regnum] != 0) + return read_memory_unsigned_integer (fi->fsr.regs[regnum], + REGISTER_RAW_SIZE(regnum)); + + return read_register (regnum); } +/* Function: skip_prologue + Return the address of the first code past the prologue of the function. */ + CORE_ADDR mn10300_skip_prologue (pc) CORE_ADDR pc; { + CORE_ADDR func_addr, func_end; + + printf("mn10300_skip_prologue\n"); + + /* See what the symbol table says */ + + if (find_pc_partial_function (pc, NULL, &func_addr, &func_end)) + { + struct symtab_and_line sal; + + sal = find_pc_line (func_addr, 0); + + if (sal.line != 0 && sal.end < func_end) + return sal.end; + else + /* Either there's no line info, or the line after the prologue is after + the end of the function. In this case, there probably isn't a + prologue. */ + return pc; + } + +/* We can't find the start of this function, so there's nothing we can do. */ + return pc; } /* Function: pop_frame @@ -87,8 +308,35 @@ void mn10300_pop_frame (frame) struct frame_info *frame; { + int regnum; + + printf("mn10300_pop_frame start\n"); + + if (PC_IN_CALL_DUMMY(frame->pc, frame->frame, frame->frame)) + generic_pop_dummy_frame (); + else + { + write_register (PC_REGNUM, FRAME_SAVED_PC (frame)); + + for (regnum = 0; regnum < NUM_REGS; regnum++) + if (frame->fsr.regs[regnum] != 0) + write_register (regnum, + read_memory_unsigned_integer (frame->fsr.regs[regnum], + REGISTER_RAW_SIZE(regnum))); + + write_register (SP_REGNUM, FRAME_FP (frame)); + } + + flush_cached_frames (); + + printf("mn10300_pop_frame end\n"); } +/* Function: push_arguments + Setup arguments for a call to the target. Arguments go in + order on the stack. +*/ + CORE_ADDR mn10300_push_arguments (nargs, args, sp, struct_return, struct_addr) int nargs; @@ -97,19 +345,89 @@ mn10300_push_arguments (nargs, args, sp, struct_return, struct_addr) unsigned char struct_return; CORE_ADDR struct_addr; { + int argnum = 0; + int len = 0; + int stack_offset = 0; /* copy args to this offset onto stack */ + + printf("mn10300_push_arguments start\n"); + + /* First, just for safety, make sure stack is aligned */ + sp &= ~3; + + /* Now make space on the stack for the args. */ + for (argnum = 0; argnum < nargs; argnum++) + len += ((TYPE_LENGTH(VALUE_TYPE(args[argnum])) + 3) & ~3); + + sp -= len; + + /* Push all arguments onto the stack. */ + for (argnum = 0; argnum < nargs; argnum++) + { + int len; + char *val; + + if (TYPE_CODE (VALUE_TYPE (*args)) == TYPE_CODE_STRUCT + && TYPE_LENGTH (VALUE_TYPE (*args)) > 8) + { + /* for now, pretend structs aren't special */ + len = TYPE_LENGTH (VALUE_TYPE (*args)); + val = (char *)VALUE_CONTENTS (*args); + } + else + { + len = TYPE_LENGTH (VALUE_TYPE (*args)); + val = (char *)VALUE_CONTENTS (*args); + } + + while (len > 0) + { + write_memory (sp + stack_offset, val, 4); + + len -= 4; + val += 4; + stack_offset += 4; + } + args++; + } + + printf("mn10300_push_arguments end\n"); + + return sp; } +/* Function: push_return_address (pc) + Set up the return address for the inferior function call. + Needed for targets where we don't actually execute a JSR/BSR instruction */ + CORE_ADDR mn10300_push_return_address (pc, sp) CORE_ADDR pc; CORE_ADDR sp; { + printf("mn10300_push_return_address\n"); + + /* write_register (RP_REGNUM, CALL_DUMMY_ADDRESS ()); */ + return sp; } +/* Function: frame_saved_pc + Find the caller of this frame. We do this by seeing if RP_REGNUM + is saved in the stack anywhere, otherwise we get it from the + registers. If the inner frame is a dummy frame, return its PC + instead of RP, because that's where "caller" of the dummy-frame + will be found. */ + CORE_ADDR mn10300_frame_saved_pc (fi) struct frame_info *fi; { + printf("mn10300_frame_saved_pc\n"); + +/* if (PC_IN_CALL_DUMMY(fi->pc, fi->frame, fi->frame)) */ + return generic_read_register_dummy(fi->pc, fi->frame, PC_REGNUM); +/* else + return mn10300_find_callers_reg (fi, RP_REGNUM); +*/ } void @@ -121,10 +439,19 @@ get_saved_register (raw_buffer, optimized, addrp, frame, regnum, lval) int regnum; enum lval_type *lval; { + printf("get_saved_register\n"); + generic_get_saved_register (raw_buffer, optimized, addrp, frame, regnum, lval); } +/* Function: fix_call_dummy + Pokes the callee function's address into the CALL_DUMMY assembly stub. + Assumes that the CALL_DUMMY looks like this: + jarl , r31 + trap + */ + int mn10300_fix_call_dummy (dummy, sp, fun, nargs, args, type, gcc_p) char *dummy; @@ -135,10 +462,26 @@ mn10300_fix_call_dummy (dummy, sp, fun, nargs, args, type, gcc_p) struct type *type; int gcc_p; { + long offset24; + + printf("mn10300_fix_call_dummy start\n"); + + offset24 = (long) fun - (long) entry_point_address (); + offset24 &= 0x3fffff; + offset24 |= 0xff800000; /* jarl , r31 */ + + store_unsigned_integer ((unsigned int *)&dummy[2], 2, offset24 & 0xffff); + store_unsigned_integer ((unsigned int *)&dummy[0], 2, offset24 >> 16); + + printf("mn10300_fix_call_dummy end\n"); + + return 0; } void _initialize_mn10300_tdep () { + printf("_initialize_mn10300_tdep\n"); + tm_print_insn = print_insn_mn10300; } -- 2.30.2